Send estimated content length if requested

engine/media_streamer.go

@@ -138,8 +138,11 @@ type Stream struct {
 func (s *Stream) Seekable() bool      { return s.Seeker != nil }
 func (s *Stream) Duration() float32   { return s.mf.Duration }
 func (s *Stream) ContentType() string { return mime.TypeByExtension("." + s.format) }
-func (s *Stream) Name() string        { return s.mf.Path }
+func (s *Stream) Name() string        { return s.mf.Title + "." + s.format }
 func (s *Stream) ModTime() time.Time  { return s.mf.UpdatedAt }
+func (s *Stream) EstimatedContentLength() int {
+	return int(s.mf.Duration * float32(s.bitRate) / 8 * 1024)
+}
 
 // TODO This function deserves some love (refactoring)
 func selectTranscodingOptions(ctx context.Context, ds model.DataStore, mf *model.MediaFile, reqFormat string, reqBitRate int) (format string, bitRate int) {

server/subsonic/stream.go

@@ -26,6 +26,7 @@ func (c *StreamController) Stream(w http.ResponseWriter, r *http.Request) (*resp
 	}
 	maxBitRate := utils.ParamInt(r, "maxBitRate", 0)
 	format := utils.ParamString(r, "format")
+	estimateContentLength := utils.ParamBool(r, "estimateContentLength", false)
 
 	stream, err := c.streamer.NewStream(r.Context(), id, format, maxBitRate)
 	if err != nil {
@@ -46,6 +47,14 @@ func (c *StreamController) Stream(w http.ResponseWriter, r *http.Request) (*resp
 		// If the stream doesn't provide a size (i.e. is not seekable), we can't support ranges/content-length
 		w.Header().Set("Accept-Ranges", "none")
 		w.Header().Set("Content-Type", stream.ContentType())
+
+		// if Client requests the estimated content-length, send it
+		if estimateContentLength {
+			length := strconv.Itoa(stream.EstimatedContentLength())
+			log.Trace(r.Context(), "Estimated content-length", "contentLength", length)
+			w.Header().Set("Content-Length", length)
+		}
+
 		if c, err := io.Copy(w, stream); err != nil {
 			log.Error(r.Context(), "Error sending transcoded file", "id", id, err)
 		} else {